Transformer



A. N. SMITH Oct. 29, 1935.

TRANSFORMER 22 2 30 31403 6 3nventor attorneg m f a a 1 2 8 2 6 a 7! a 5. 3 0 N 6 6 J 20 0 6 a 4 2 w e 2 1 Oct. 29, 1935. A. N. SMI'T 2,019 96 TRANSFORMER Filed Dec. 27, 1935 2 Sheets-Sheet 2 v f Mnnentor (Ittorneg Patented Oct. 29, 1935 I UNITED STATES 2,019,190 'raansroausa Anthony Smith, Glrard, Pa... alsignor to m Girard Model Works, Ina, Girard, Pa a corporation of Pennsylvania Application December :1, loss, Serial No. 104,111: 11 Claims. (01. 111-119 This invention relates to electrical apparatus. particularly to control apparatus for regulating a supplyof current to electrical translating devices.

The present disclosure deals with an embodiment wherein the apparatus .is designed to permit manual regulationand control of current therein, between an in-put and out-put.-

An object of this invention is the provision in an apparatus of such character, of a novel sliding contact with the control and the mounting therefor.

Another object is the provision, in such apparatus, of a self-contained coil mount and a sliding contact member adapted for support within a separable section casing.

A further object is the provision, in such apparatus, of a separable casing having sliding contact actuator means supported therein in slidably straddled engagement with a casing wall. Other objects will be apparent from the description. The present disclosure constitutes an exposition of the invention as reduced to practice. It is to be understood that the structural details thereof may be varied to any extent not inconsistent with the scope of the invention as claimed.

In the drawings:

Figure 1 is an assembled perspective view of a structure made in accordance with the invention. Figure 2 is an internal elevation with a section of the separable casing removed.

Figure 3 is a section taken on the line 3-3 of Figure 2.

Figure 4 is a dis-assembled perspective view of the various parts of the structure illustrated.

The invention is applicable to any current regulating devices, as for example, transformers, rheost-ats, tuners, variable inductances and the like. The herein disclosed embodiment illustrates an application in connection with a transformer windings I4 and I 5 respectively. As shown in the drawings the secondary winding is composed of two layers of suitable wire, being separated from each other by the insulation It. The secondary piece 33.

Ros sun) winding encompasses the primary and is insulated therefrom as indicated at l1 nor in any well known manner. The arrangement of the secondary winding into two layers permits of the 1 outside layer carrying only one-half of the total vvoltage, or in other words, one half maximum to minimum. It is to be understood, however, that the coil may be so constructed that the entire'range from minimum to maximum may be had by the use of one layer. m

The coil ii is rigidly secured within an open- 1 ing it formed by laminated core sections is thus forming a unitary structure or coil \mit. To secure and properly position this unit within the housing, I have provided a frame 20 of substan- 1s tially 'U-shaped construction. The coil unit, which embraces the laminated sections and coilper se, is held within the frame and restrained against movement therein by means of the side flanges 2 I and the top portion 22. The top per 20 tion is provided with tongues 23 for engagement with the sides 2| through slots 25 formed therein. These tongues are twisted as distinguished from being bent at right angles in order to project laterally and serve to space the frame and coil as from the housing, as clearly shown in Figures 2 and 4.

Depending legs 28, formed from the bottom portion of the frame, are secured to upon the base I! in a manner to space the frame so' therefrom. Tongues 21, integral with the legs 28 pass through slots 28 in the base for securely holding the frame thereto. The tongues, as a matter of'course, being bent at right angles to perform this function.

Pivot bearings 28 in the form of depending flanges are formed from the bottom portion of the frame and are provided with openings therein for the reception of a pivot pin or shaft 3|.

The shaft ii has mounted thereon acomposite switch device which comprises an actuator, such as a finger piece 3i, a contact element II and an insulating strip or -means 8|, -The finger piece, as illustrated, is composed of a flat strip 5 g of metal, although insulating material could be used, having a lower portion 38 formed at right angles thereon, the end 31 thereof being turned upward and provided with a shaft opening ll. A similar opening 39 is also formed in the finger 50 The lower portion 88 of the finger piece is provided with slotted openings 40 for the reception of the bifurcated end ll of the insulating strip 85, which construction securely holds the strip to the finger piece for movement there- Y with. A suitable pivot opening 42 is provided in the insulating strip 35 for the reception of the shaft 3|.

The contact element 34 comprises a bowed strip of resilient metal, slotted as at 43 to form thereon a tongue 44. A depressed or indented nub 4B is positioned on the end of the contact element to actively form electrical contact between the contact element and the outer second-\ ary winding of the coil as will be hereinafter set forth.

Interposed between the contact element 34 and the insulating strip 35 is a terminal connector 41, which is held therebetween by means of a rivet 48 which passes through openings 49 and 50 in the contact element and strip respectively. A projecting portion 5| on thetongue ll fits within a slot 32 in the strip 35 and prevents relative movement between the strip and contact element.

At one side of the convolutions of the coil and .flush therewith is mounted a flat strip of insulating material to form and function as a circuit cut-off 52. A suitable mounting 54 secured to one of the laminated sections serves to properly position the cut-oil, the mount being provided with tongues 53, to rigidly hold the strip thereto The bottom section or base I2 carries the end walls 55 of the housing structure and these walls are provided with tongues 33 formed on the upper ends thereof, these tongues being so arranged as to be receivable through the slots 51 formed in the cover II. The end walls of the frame 20 'are also provided with tongues I3 receivable through slots 53 in the cover. When the housing sections are assembled, thetongues 33 and 53 project through the slots 51 and 53 respectively and are bent at right angles in a manner to securely hold the parts together.

The base I! is so formed, as to provide a pair of upturned flange members 83 which properly position the cover II when assembled. Similar flange members iii are formed on the ends of .the cover and serve to prevent any spreading of the end walls of the base or bottom section.

A downwardly extending cup shaped portion 62 is formed on the bottom of the base in a flange 60 in a manner to permit of the free movement of the switch device, the cover being provided with adepressed portion 83 adjacent the cup shaped portion on the flange I to cooper-' ate with the same for the free movement of the switch device. Suitable stops '4 formed on the front of the cover limit the movement of the finger piece 33.. It will be noted that the front face of the cover carries a rib or guide I projecting inwardly in a manner to space the insulating strip away from the side wall of the cover. This rib functions to force the insulating strip towardsthe coil, and as a consequence of this action, the contact element, which is secured to the strip, is tensioned against'a' portion of the secondary winding of the coil or the cut-off 32, as the case 1 may be.

The end walls of the base are provided with openings 66 and 81 which receive respectively the in-put cable a to the primary and the output terminal posts. A suitable cable 33 connects terminal connector 41 to a secondary or out-put terminal post 63 positioned in one of the openings 31, the same being insulated from the end wall. It can be readily understood from this'arranflement of the parts, thatvthe switch device is interposed in the secondary circuit and to place the finger piece in order to obtain any 5 desired voltage within the range provided by the secondary windings on the-coil.

It will be noted that the frame is held in spaced relation to the housing, and that the top portion 22 is provided with cut-away por- 10 tions, in order that a free circulation of air may be obtained to assist in cooling the coil unit.

In operation, the parts being assembled as shownin Figures 1 to 3 inclusive, the movement of the finger piece and associated parts towards 15 the cut-ofl 5; will reduce the amount of voltage imparted through the secondary circuit as a small number of convolutions of wire on the secondary winding of the coil are in the circuit.

It also follows that movement of the finger piece 20 in the opposite direction will increase the amount of voltage as more convolutions are in the circuit. Continued movement of the finger piece towards the cut-oil I! will position the contact element on the insulating strip and break the 25 circuit.

Cable 88 connects one side of the secondary coil with the terminal post 63 and the other side of the secondary coil is connected through wire II with a terminal post,not shown, mounted on a wall of the base I! adjacent the terminal post I3.

The insulating strip 35 provides a. mounting for the spring tensioned contact finger 34 and serves to maintain the contact finger out of any electrical contact with any portion of the casing structure. This insulating strip 35 is attached to the bight 38 in such manner that the insulating stripis moved by and in conJunction with the actuator arm or finger 33. Both actuator finger 33 and the insulating strip 33 are pivoted on the pintle 3|v for free movement with respect thereto. The edge of the casing section ii is suitably slotted adjacent the depressed portion 63 to accommodate the disposition of the pintle 3|. 45

A feature of the invention resides in the fact that the actuator arm 33 and the insulator strip 35 straddle the adjacent edge of the casing cover section I l in slidable relation to the opposed faces thereof. The cover section II is applied and 50 disengaged by sliding between the actuator finger 33 and the insulator strip. This insures a positive disposition of the actuator finger on the exterior of the casing. It will be apparent that in this assembly the actuator and the contact 65 finger are pivotally mounted upon. the coil carrying frame and these elements do not have any connection either electrical or mechanical with either of the separable casing sections. In this construction no part of the secondary circuit 60 passes through the actuator finger 33 or its pintle 3|.

What I claim: 1

1. In a current regulating device having a casing comprising base and closure sections, said 05 closure sections providing a casing wall, a coil mount therein and secured to the base sections, and a conductor coil in said mount; means for establishing slidable contact with the conductor coil, means disposed externally of the closurebetween said contact establishing means and the moving means therefor at one side of thepivot,

said moving means straddling the lower edge of said closure provided casing wall adjacent said base whereby to admit of ready removal of the casing without interference with said moving means.

2. In a current regulating device having a casing, a coil mounttherein, and a conductor coil in said mount; means for establishing contact with the conductor coil, an insulator member supporting said contact means, means on said coil mount providing a pivot for said insulator member, an actuator member having a portion pivotally connected to said pivot providing means, means supporting said actuator member on the coil mount, said actuator straddling a lower edge portion of a wall of said casing and havinga portion disposed externally of the casing and unsupported thereby, and said insulator member having a fixed connection with said actuator member within the casing.

3. In a current regulating device, a casing, a coiled conductor therein, means supporting and anchoring said conductor in the casing in spaced relationfrom the .walls thereof and comprising outwardly extending tongues, a manually operable contact member, means carried by said conductor supporting means and providing a pivotfor said contact member, means externally of said casing for moving the contact member on its pivot over the conductor coils and supported solely by said pivot providing means, and an operating connection between said contact member and its moving means.

4. In a current regulating device having a casing and a conductor coil supported therein; a

pivot pintle, a strip of insulating material freely pivoted on said pintle, an actuator finger freely pivoted on said pintle, means operatively connecting said strip and finger in fixed relation, 8. contact element carried by said strip-and spaced from said pintlev in slidable engagement with said conductor coil, and said actuator finger and insulating strip straddling a wall of the casing in slidable unsupported relation.

5. In a current regulating device, a separable sections casing, a coiled conductor therein, a take-off contact member having sliding contact with the conductor coils, a support for said vconductor, a pintle carried by said support and clear of the sections of said casing to permit ready separation and assembly thereof, an insulator member pivoted on said pintle, said contact member being carried by said insulating member, an actuator for said contact member pivoted on said pintle and disposed over the exterior of .the casing, and an operative connection between said actuator and insulator member internally of the casing.

6. In a transformer structure, a casing, a

vary the voltage of current through said lead.

7. In a transformer structure. a separable housingjatransformer coil located therein, a

secondary lead for said coil, a switch device asg that the voltage of current passing through said lead may be varied upon movement of said finger piece.

8. In a transformer structure, comprising a separable housing, a transformer coil within said housing, a secondary lead for said coil, a frame for holding said coil and spacing the same from said housing, said transformer having a finger a0 piece, a contact element, and insulating means securing said contact to said piece, aterminal connector interposed between said piece and said means and connected to said lead, and said contact element engaging said coil in such manner that the voltage of current passing through said lead may be varied upon movement of said finger piece.

9. In a transformer structure, a housing, a transformer coil within saidhousing, a secondso ary lead for said coil, a frame for holding said coil and spacing the same from said housing, a switch device associated with said coil and operatable without said housing, meanspivctally connecting said switch device to said'frame, said I switch device having a finger piece, a contact element, and insulating means securing said contact to said piece, a terminal connector interposed between said piece and said' means and connected to said lead, and said contact element 40 engaging said coil in such manner that the voltage of current passing through said lead may be varied upon movement of said finger piece.

10. In a transformer structure, a housing, a transformer coil within said housing, a secondary lead' for said cell, a frame for holding said coil and spacing the same from said housing, a switch element contacting said coil within said housing and operable without said housing,

means connecting said element and said lead, 60

means isolating said element from said housing and normally urging said element towards said coil, and means controllable without said housing for positioning said element relative to said cell in such manner that; the voltage of current passing through said lead may be varied.

11. In a transformer structure, a housing, a transformer coil having an exposed secondary winding positioned within said housing, a secondary lead for said coil, a contact element engaging said winding and connected to said lead. a finger piece for moving said contact element across the exposed surface of. said winding, insulating means connecting said element to said a piece and means co-acting with said fingerpieoe for indicating the position of said element -relative to said winding. j l

. ANTHONY N. SMITH. 

